When you launch the app, the first screen you see is a linked table of contents:
The Reflection section is an exercise in mindfulness, as the Web page announcing the Bullet Journal Companion app notes:
Keeping track of what you need to be doing is important. Keeping track of why you’re doing those things is critical. Reflection will help keep you focused on the why through daily trackable reminders prompting you to unplug and review your notes.
The idea is that you set an AM and PM time to reflect each day on why you’re doing what you are doing. There are several inspirational quotations, and you can “log” or track the fact that you did in fact reflect by tapping a calendar date. If you set up Notifications, the Bullet Journal Companion will remind you to reflect. I’m not one to find this appealing, but others may.
I think that the purpose of the Library is to allow you to use your iPhone’s camera to take photos of a BuJo® page, give the Bullet Journal app permission to use the photo, and then associate it with a specific journal, date range and one or more tags to create a digital index of sorts. The search function appears limited to tags, rather than actual contents. I suspect that there are plans to allow OCR or some better ways of locating data than tags; as it stands it’s not terrible useful, and it’s certainly not innovative (see for example EverNote or Moleskine notebooks and app or Baron Fig notebooks and Codex.app.
Most of the articles appear to be also available on the official BulletJournal Website, though I admit I can’t find the one on Reflection on the site. The articles are a useful resource, especially for those getting started.
This appears to be an overview of the Official Bullet Journal notebook, also sold from the Website, but it doesn’t appear to be an actual store in terms of being able to buy one from your iPhone.
The Guide has merit for those starting out, but not $2.99 worth. The free .pdf Starter Guide you can download when you subscribe to the Bullet Journal Newsletter is, in my mind, more helpful. I’m not outraged at spending $2.99, but the Bullet Journal Companion app strikea me as somewhat useless; it’s not going to stay on my phone.